NFL quarterback passing in freezing cold

Across 4,555 outdoor starts by 107 quarterbacks from 2006 to 2025, passing output rises by about 0.30 yards per degree of temperature — a real but shallow gradient that only bites hard at the extreme. Below 20°F a starter throws -21.7 yards against his own season form, with completion rate -2.94 points lower and -0.28 fewer touchdowns — all three clear significance. Ordinary winter cold (32–45°F) costs roughly 8 yards. Interceptions and sacks do not move in any band.

The top figure in each cell is the raw band average; the smaller figure is the gap against the quarterback's own season baseline, with its t statistic. Anything under roughly 2 is noise and is greyed out. The 40-start minimum was fixed before any band was inspected and is applied to every study we publish.

Two honest caveats. First, the warm and hot rows are positive by construction — a quarterback's baseline includes his own cold-weather starts, so the warm and cold rows are mirrors of each other, not independent results. Second, the coldest games are also the windiest (the severe band averages 9.1 mph against 7.1 mph in heat), and the calm-wind column shows how much of the "cold" effect is really wind: in severe cold the yardage gap shrinks from -21.7 to -9.5 once windy games are removed. The remainder points the same way but is no longer significant on its own — we report it as direction, not as a number to price.

League passing has drifted upwards across the window: outdoor starters averaged 209.2 yards at 6.88 per attempt in 2006 and 214.6 yards at 7.11 per attempt in 2025. A study that pooled two decades against a single league average would hand weather the credit for rule changes and offensive evolution. Because each baseline is built inside a single season for a single quarterback, that drift cannot reach the temperature comparison at all.

• Severe cold is real. Under 20°F, yards, completion rate and touchdowns all fall significantly against the same quarterback's season form — the only band where every measure moves together.
• Ordinary winter cold is modest. From 20°F to 45°F the yardage cost sits in single digits, and completion rate does more of the moving than volume.
• Mistakes do not rise. Interceptions and sacks sit flat in every band, matching the turnover study and the wind study.
• Wind is the confound to watch. The coldest games are the windiest, and the calm-wind split shows a large share of the severe band's gap travelling with the wind rather than the thermometer.
• This is why scoring stays flat. Cold suppresses passing efficiency; teams compensate elsewhere. The quarterback pays for cold weather more than the scoreboard does.

• Sample: 4,555 outdoor starts, 2006–2025. A start qualifies when the passer threw the most attempts for his team, attempted at least 10 passes, and logged at least 8 such games that season so his baseline is stable. Domes and closed roofs are excluded entirely rather than used as a control.
• Weather: hourly reanalysis at the stadium's own coordinates, temperature taken at kickoff, game-window wind reported alongside every band and used for the calm-wind split (under 10 mph).
• Baseline: leave-one-out mean of the same quarterback's other qualifying starts in the same season, computed separately for yards, yards per attempt, completion rate, touchdowns, interceptions and sacks.
• Not controlled: opponent pass defence, game script and score differential, precipitation, play-calling, and receiver availability. A team that abandons the pass in a freeze shows up here as fewer yards, which is part of the effect we are measuring rather than a separate one.
• No prop or betting lines are attached to these starts, so this study reports performance against a quarterback's own form and makes no claim about whether the market prices cold correctly.

Data generated 2026-09-27. Numbers refresh as the archive tops up; corrections are dated and kept visible.

• NFL Temperature & Scoring — the deliberate null this study explains: cold moves the quarterback, not the scoreboard.
• NFL QB Passing in Wind — the companion study: wind is the condition that genuinely moves passing, and the confound inside every cold-weather game.
• NFL Turnovers in Bad Weather — why cold and wet football does not mean extra giveaways.

• Open-Meteo ERA5 historical reanalysis — archive-api.open-meteo.com (hourly game-window weather at each venue’s own coordinates)
• ESPN NFL scores and odds — espn.com/nfl (schedules, final scores and consensus closing totals)
• Internal NFL historical game archive — venue identity, roof status and final scores.
• Internal NFL quarterback boxscore archive — per-start passing lines parsed from public boxscores.
• Every dated change we have made to a published study is listed on our corrections log.